I intended to sell the 2.5 and the CV 1.5 to fund the APO. I bought the APO, sold the 2.5, and held onto the 1.5 even though I hate its haptics. I love the APO but, honestly, either the 2.4 or the 2.5 would complement the 1.5 nicely.
As much as I covet both the 75 and 90 APO, there is certainly a penalty in the form of size, weight, and of course price. I like how compact the Summarit is, takes very little space in the bag. But who am I kidding... I'll probably end up with an APO at some point!
I too had the VM 75/1.5, and although I found the IQ to be fantastic, I was not a fan of the size and haptics. And 58mm filters....? Although I did like that due to the design of the aperture ring, I could easily extrapolate what f/stop I was at while looking through the rangefinder!
In the meantime, I recently went even further as far as size & weight, and picked up a 90/4 Macro-Elmar that came up locally for a pretty good price. Again, very little space in the bag.
I like how compact the Summarit is, takes very little space in the bag. But who am I kidding... I'll probably end up with an APO at some point! 
